Plot Summary:The once famous and well respected scientist Zorndyke has bred a new genre of living being, one that thrives on the oceans and lives to destroy humans. Zorndyke believes it is time that the humans were relieved of their rule of the earth. It is up to Blue Submarine No. 6 and the rest of the Blue fleet to put an end to Zorndyke's madness and creations.

Plot Summary:Enter Sentan, a lush, tranquil island encased in war between the military and those with Hiruko, known as X'amd. On one of these warlike days, Akiyuki Takehara heads off to school and gets caught in a raid by the creatures. Through a series of events he is transformed into a X'amd, and with the help of a Tessikan woman Nakiami along with his highschool friend Haru, Akiyuki is forced to learn to live with the Hiruko or faces the danger of losing his self-control and turn to stone.